This invention relates to an inertia damper and a method for manufacturing the same, and more particularly to an inertia damper adapted to be incorporated in a device, such as a stepping motor widely used as a drive source for office automation equipment, various kinds of automatic production units or the like, to converge vibration of the stepping motor during the step response of the stepping motor and transient vibration of a rotary shaft of the stepping motor and a method for manufacturing the same.
A stepping motor which exhibits excellent functions such as accurate driving, rapid stopping, rapid starting and the like has disadvantages that the transient response during rising at the time of starting rotation is apt to be vibratory and unstable phenomena such as resonance in a fixed frequency domain of a drive power supply and the like fail to permit the rotation of the motor to be smoothly carried out. Accordingly, in order to properly drive equipment by the stepping motor, a mechanism for eliminating such disadvantages is necessarily required. In view of the foregoing, the inventor has developed an inertia damper utilizing a gel material that it exhibits good vibration absorbing characteristics. In the proposed inertia damper, a mount base is mounted on a rotary shaft of a motor. However, the inertia damper fails to exhibit sufficient endurance under various operating conditions. More particularly, the proposed inertia damper, as shown in FIG. 1, includes a mount base 28, an inertia weight component 30 and a gel material 32 and is constructed in such a manner that the mount base 28 and inertia weight component 30 are connected to each other through the gel material 32 arranged between the inner peripheral surface of the inertia weight component 30 formed into an annular shape and a boss 36 of the mount base 28 in a vibration absorbing manner. Thus, in the conventional inertia damper constructed as described above, a space in which the gel material 32 is arranged is formed into relatively small dimensions, so that the gel material 32 may very satisfactorily absorb vibration of a small magnitude. However, such construction fails to cause the gel material 32 to exhibit satisfactory absorption of vibrations of a large magnitude, as well as exhibit good endurance under the operating conditions where a large amount of vibration energy is applied thereto.
The present invention has been made in view of the foregoing disadvantage of the prior art.
Accordingly, it is an object of the present invention to provide an inertia damper which is capable of exhibiting satisfactory endurance even under the operating conditions where an excessive load is applied to the inertia damper. It is another object of the present invention to provide an inertia damper which is capable of satisfactorily absorbing vibration of a large magnitude. It is a further object of the present invention to provide an inertia damper which is capable of accomplishing the above-described objects with a simple structure.
It is still another object of the present invention to provide a method for manufacturing an inertial damper capable of exhibiting satisfactory endurance even under the operating conditions where the excessive load is applied to the inertia damper. It is a still further object of the present invention to provide a method for manufacturing an inertia damper which is capable of easily providing an inertial damper.
In accordance with one aspect of the present invention, an inertia damper is provided which comprises a mount base, an inertia weight element and a gel element. The mount base and inertia weight element are coupled to each other through the gel element in a vibration absorbing manner. The mount base is formed on the outer periphery thereof with a peripheral cover section to define a housing space therein for receiving the inertia weight element. The gel element is interposed between the outer peripheral surface of the inertia weight element and the inner peripheral surface of the peripheral cover section to couple the inertia weight element and mount base to each other in a vibration absorbing manner.
In accordance with another aspect of the present invention, a method for manufacturing an inertia damper is provided. The method comprises the steps of setting an inertia weight element and an inner sleeve in a mold in a manner to be spaced from each other at a predetermined distance, pouring a gel material between the inertia weight element and the inner sleeve and curing the gel material to form a gel element and constitute a unit comprising the inertia weight element, inner sleeve and gel element, forming a mount base, incorporating the unit into the mount base, covering the mount base with a lid, and subjecting the mount base and lid to assembly to carry out welding between the mount base and the inner sleeve and welding between the inner sleeve and the lid.